This invention relates to a corkscrew, and more particularly to a corkscrew having a handle mounted to a screw stem which is rotatably guided within a cap.
Corkscrews have been known for centuries. A particular type as disclosed in U.S. Pat. No. 310,766 (B. Wilhelm) includes a handle mounted to a cone-shaped part, the bottom of which has a circular groove for receiving two semi-circular tongues. These tongues surround a screw and form the upper ends of loose prongs having inner shoulders that are capped by a slidable ring. A screw stem comprising a bearing disk is fixed to the handle so as to axially hold the components together. In operation, the screw tip is turned into a cork and the ring is slid up or down, respectively, so that the lower prong ends will first be spread and then moved together as lower prong shoulders are placed onto the neck of a bottle. Further turning of the handle will force the cork up between the prongs while the device is pressed onto the bottle.
More modern corkscrews of similar type include a housing or bell that is solid with two prongs. These modern corkscrews have inner semi-circular stops to be placed onto a bottle neck. Under a firm grip to hold the bottle and housing together, a loose screw or worm can be put through a housing top portion that serves for guiding the screw which, upon turning, will enter the cork. As the latter raises between lateral ribs of the housing, it will thereby be held against rotation; once it is lifted out of the bottle, simple counter-turning of the screw handle will eject the cork from the bell.
Other corkscrews named after Reissmann have a tapped stem screw borne within a matching tapped bush of a bell or housing. A tiltable top nut through which a handle rod extends transversely also screws with the stem thread. With the housing bottom put onto a bottle neck, the handle is turned one way from a first upper position so as to penetrate the cork, and under continued turning the handle will screw down on the stem and the cork is extracted from the bottle; then the nut is tilted, the handle is turned upwards the other way and turning is continued until the cork drops out from between retaining bell ribs.
While each of the foregoing designs has its merits, there are specific drawback thereto. Thus, the corkscrew initially described requires precise manufacture and mounting, and the assembly of the various components is critical in that both close fit and rotatability are of the essence for trouble-free use. In addition, there are no centering means for the screw which is thus quite likely to sometimes obliquely enter a cork. Solid bells cannot fit bottle necks of widely differing sizes. Conventional Reissmann corkscrews, in particular, have a short housing pot that will not readily warrant centered application to a corked bottle so that it may again be possible to penetrate the cork in a slanted direction, resulting in its split-up.
The present invention aims at overcoming these and other drawbacks of the prior art.
It is an object of the invention to create a corkscrew that combines advantages of earlier designs in a simple and economical manner.
A particular object of the invention is the creation of a two-prong corkscrew of sturdy design that permits fairly cheap manufacture and ease of use; especially with well centered application onto bottle necks of various sizes.
It is another object of the invention to provide a corkscrew having a screw which is surface-treated for minimum friction and is designed fore easy piercing into a cork and for providing a large engagement area therein.
Various features of the invention are recited in the appended claims.
Thus, in accordance with one aspect of the invention, there is provided an improvement in a corkscrew including a handle mounted to a screw stem rotatably guided within a cap which contains upper ends of two prongs having semi-circular lower ends that surround a screw and comprise inner shoulder stops adapted for engagement on a bottle neck. The improvement is particularly characterized in that the upper prong ends are articulated to a core unit to which a guide bush for the screw stem is associated, and in that the prong ends are spring-biased to provide a spreading force towards the perimeter of the cap.
The above noted feature is of significance in permitting very easy application of the corkscrew to bottle necks of widely varying diameters which are gripped by the prongs for centered engagement of the screw to a cork to be extracted therefrom. The cap may be integral with the handle, or the latter may be screw-fitted to a tapped stem which is guided by the cap.
The core unit may include bearing means for the upper prong ends on which expanding springs bear and which have and/or find stops in the region of a lower peripheral edge of the cap.
More particularly, each of the upper prong ends may comprise a lug for support on a pin which traverses guiding cheeks of the core unit on either outward side of the guide bush.
Cork retaining and removing means in a bell may include radial ribs having lower leading edges in each central portion of the prongs. Various types of screws or worms can be exchangeably used. Preferably, a bladed type is used, having wide sharp flares or a round wire hollow helix, either one ending in a pointed tip. Still more particularly, the screw is preferably made of steel and is surface-treated for minimum friction, e.g., by plating, enameling or teflon-coating.
The screw may conically widen downwards, and thus be captive in respect of the core unit in which it is guided.
These and other objects, features and advantages of the present invention will become readily apparent to those skilled in the art from the following description and drawings, wherein there is shown and described a preferred embodiment of the invention, simply by way of illustration and not of limitation of one of the best modes (and alternative embodiments) suited to carry out the invention.
The invention itself is set forth in the claims appended hereto. As will be realized upon examination of the specification and drawings and from practice of the same, the present invention is capable of still other, different, embodiments and its several details are capable of modifications in various obvious aspects, all without departing from the scope of the invention as recited in the claims. Accordingly, the drawings and the descriptions provided herein are to be regarded as illustrative in nature and not as restrictive of the invention.